Cube Stereo Super HPC Race

The only thing squarer than a square is a squared-square, otherwise known as a Cube. With its origins in Germany, a country sometimes accused of fostering a fairly conservative (dare we say it, square) mindset, you might expect that the Cube Stereo, which sounds like two squared-squares coming at you from both sides, would be a bit, well, square as well.

Well put that idea squarely out of your head because beyond the name, there’s little about the Cube Stereo HPC 160 Race that isn’t distinctly outside the box in terms of bike design and manufacturing. Okay, enough of the square jokes; aimed at the burgeoning gravity enduro scene, this completely redesigned, 160mm travel full carbon-fibre creation is designed to pedal well on the flats and the ups, and utterly smoke the turns and the downs. The Race spec is the entry-level version of the Stereo, and whilst there’s no such thing as a cheap full-carbon dually, the asking price of $4,999 is not unreasonable. Components are a pretty mixed bag, with suspension from Fox, drivetrain by Shimano, brakes by Formula, and the post/bar/stem combo from Easton—the Haven Carbon handlebar is a highlight with most other parts from the more ‘value’ end of their respective stables.

Cubes New Triangles

We’ve said it before and we’ll say it again; the frame and suspension are the heart of any bike—a good frame with cheaper components is much better than the other way around. The truly astounding thing about the Stereo 160 frame is its weight; at 2,234g (medium size) including the shock it’s competitive with many 100mm travel carbon fibre XC bikes and at least a few hundred grams lighter than anything else we’ve seen in this travel category. It doesn’t sport the absolute stiffest rear triangle out there but it’s far from being a noodle, and the main frame is very solid at both the bottom bracket and head tube. We can’t comment on long-term durability or crash resistance, but Cube have a solid reputation for quality bikes, so there’s every chance it’ll hold up well to the rigours of day to day use.

Not only is the new Stereo 160 light and stiff, but it’s got a host of mod cons to boot; the dropouts are tied together with an X-12 style thru-axle, there’s 180mm post mount rear brake tabs, a direct mount front derailleur and a 92mm press fit bottom bracket. The shift cables run internally through the down tube, there’s a long rubberised strip under the down tube that helps to fend off rock strikes and the headset bearings fit directly into the moulded carbon head tube. There’s also routing for a ‘stealth’ style dropper post, however somewhat oddly there are no cable guides should you want to run a post with external routing, which effectively rules out most posts currently on the market. Another strange omission is the lack of ISCG tabs so there’s no real option to fit a chain guide; given the bike’s enduro intentions this doesn’t make a lot of sense to us. It is nice, however, to see room for a bottle cage inside the frame, and the direct mount rear derailleur hanger (which eliminates the short upper link on Shimano Shadow derailleurs) is also a newer innovation we’d like to see on more bikes in the future.

Frame geometry is also very much up to date, and it’s been specifically designed to work with the wheel size du jour, 27.5 (650B). The 66.5-degree head angle would have been considered suitable for a downhill bike five years ago and it gives bucket loads of stability when things get fast, steep, or hairy. The 74.6-degree seat tube angle helps keep your weight relatively centred on seated climbs so you don’t need to scoot forward and risk the nose of the saddle intruding into your nether regions. The chainstay length of 441.5mm is a little longer than the most avant-garde designs, but where Cube have really pushed the envelope is the bottom bracket height; it sits 14mm below the axles which yields an unsagged height of about 335mm with stock tyres. Long, low, and slack may be where it’s at, but this is as low a bike as you’re likely to find—we’ll discuss the implications of this further down the track, but suffice to say that the Stereo 160 is certainly pushing the boundaries in this area.

In terms of design and construction quality, Cube has done a great job with their new enduro baby. The lines are clean and straight rather than curved and swoopy, internally the tubes are neat and smooth, and none of the pivot hardware screws directly into the frame, so stripping a thread isn’t going to be an expensive lesson on why you should’ve used a torque wrench. The main pivot has been pushed out as wide as it can go to help boost stiffness, however the axle and bearings are much smaller than we would have expected; only time will tell if this weight-reduction strategy causes issues with bearing life. We like that the cover over the shift cables’ exit window is nice and big, so replacing a cable won’t have you cursing whilst you fish around inside the down tube for hours. The 2.35 tyres still have room for a bit of mud without hitting the frame, no doubt a nod to the often damp trail conditions of the northern hemisphere. There’s no shortage of branding and other technology descriptors on the Stereo 160’s frame, but we still think it’s easy on the eyes and the classic black, white and red colour scheme won’t date too quickly.

The Parts Puzzle

Whilst there’s no doubt in our minds that the Stereo 160 is intended for gravity enduro riding, some of the parts chosen for this model seem quite at odds with its descent oriented personality. We’ve already mentioned the lack of chain guide tabs, but the fitting of a triple crankset seems all the more strange. Yes, you can take off the big ring and replace it with a bash guard, but then you’ll also be wanting to replace the stock 32T ring with something along the lines of a 36T; why this wasn’t done at factory level is a mystery.

Despite having had pretty good experiences with Formula brakes of late the ‘RC Tune’ model didn’t really gel with us. This is a special ‘made for Cube’ edition of the RX brake that’s fitted with both reach and contact point adjusters. Although the overall modulation was good, they had an inconsistent feel at the lever and were lacking in overall power despite needing more finger effort than many others on the market. Also, these days a dropper post could be viewed as an essential component for this style of bike. We’d have preferred to see a downgrade in the drivetrain to something like Shimano SLX (or even Deore) to allow the inclusion of a dropper post; the Stereo won’t fully reach its potential without one.

The wheels fitted to the Stereo 160 are made for Cube by DT Swiss; the ultra-reliable star ratchet rear hub is totally silent when freewheeling, although it uses the older 18-tooth ratchet for engagement every 20-degrees instead of the newer and much faster engaging 36-tooth version. The inner rim profile and included airtight rim tape means all you need to set them up tubeless is a few scoops of sealant, and once seated ours held air very well. DT seems a bit slow to come to terms with the benefits of properly wide rims. Whilst the inner width of 22mm isn’t terribly narrow, it doesn’t give the same lateral support as a rim around the 25mm mark—this is where you can start to use really low tyre pressures without suffering excess squirm or roll under hard cornering. We can, however, happily report that the rims have stayed true and ding free despite some fairly rocky test terrain, and the Hans Dampf tyres are a favourite all-rounder that you won’t need to change until they wear out.

The inclusion of an adjustable travel Fox 34 TALAS on the Stereo 160 adds a degree of flexibility to the overall package. It allows the front end to be lowered for long, steep climbs where the front end might otherwise tend to wander, especially given the slack head angle and long front centre. For 2014 Fox has redesigned and simplified their TALAS travel adjust system with the aim of reducing fork stiction, which is always an issue when you start adding extra seals and other complexities to the air spring. Despite this, our test fork was very notchy when new and although it did get better the longer we rode it, it’s never going to be as smooth and supple as an equivalent fixed travel fork. This is a bit of a ‘damned if you do, damned if you don’t’ scenario so we’re not criticising Cube for their choice, merely pointing out that the enhanced seated climbing ability of the TALAS fork comes at the expense of compliance on small to medium bumps—if it really bugs you then look to an aftermarket fork swap.

Turn Up the Stereo

Probably the first thing that strikes you about the Stereo 160 is how well it pedals; despite the long legs there’s certainly no mush fest when you spin the cranks. We’ve come across plenty of bikes with significantly less travel that don’t motor the way the big Cube does, and this undoubtedly makes the bike far more versatile than the travel and geometry figures would have you think. Our test bike weighed 12.6kg without pedals, and with such a low overall weight there’s no reason why you can’t use the Stereo as a burly day-to-day trail bike, especially if your trails tend to be the winch and plummet variety.

There is definitely a sense that this pedalling efficiency is created by a slightly firmer compression tune on the rear shock, so on chopped out and rocky terrain in definitely gives up some plushness in favour of efficiency. Because of this we primarily used the Descend setting on the CTD shock, only using the middle Trail position for relatively groomed trails or fire roads—the Climb setting is best saved for bitumen in our opinion. The 27.5 wheels on the Stereo 160 do technically have better rollover than a 26-inch wheel but the difference is very minor, and with the aforementioned firmer shock tune taken into account it doesn’t provide as smooth a ride as you might otherwise expect.

There’s plenty of support in the middle of the travel to pump into berms and depressions without feeling like you’re wasting your effort by pushing into a sponge. It’s also an easy bike to launch into the air, and once there it feels light enough to move around without getting unstable. It does, however, have a very linear compression ratio so the end of the travel comes about more readily than you might expect—we unexpectedly and very definitely bottomed out the shock on several occasions so it’s not the best big hit bike we’ve ridden lately despite the 160mm of travel on offer.

The other dominant factor in the ride of the Stereo 160 is its very low bottom bracket. Combined with the longish chainstays and the long front centre created by the slack head angle you end up with an incredible amount of stability at speed. In rough or steep terrain it’s utterly unflappable, and it’ll let you flip from rail to rail through open turns like a slot-car driver. If low is pro, then the Stereo 160 is about as pro as it gets. Of course there’s no free lunch in the bike game, and the flip side of this incredibly low bottom bracket is a dramatic increase in the incidence of pedal strikes. It’s most noticeable when climbing through baby heads and narrow chutes, but even on downhills we managed to smack the pedals on familiar trails where we’d never before even considered it a possibility.

Designers generally build bikes that work on the trails they’re familiar with, and Europe has a predominance of bike parks and groomed trails with long grinding climbs and steep descents. With that in mind it seems only logical that the Stereo 160 truly excels on this type of terrain; the long and low slung stance lets you build and maintain speed on terrain where a downhill bike wouldn’t be out of place, and it’s as comfortable on berms and jumps as a frosty stein at Octoberfest. Once you remove the pedal obstacles you’re free to spin away right to the top of the trail, and then come screaming back down as fast as you dare. It’s not the best bike we’ve ridden on natural trails, but on its home turf the Cube Stereo 160 combines low weight, pedalling efficiency and a nonchalant disregard for steep terrain that not many other bikes can match.

Thumbs Up

Bomber stability yet still agile

Insanely light frame for the travel

Efficient to pedal

Thumbs Down

Not as plush as the travel figure suggests

Bottom bracket too low for some trails

Fork harshness

Specifications

Frame: HPC Monocoque Advanced Carbon

Shock: Fox Float CTD 160mm Travel

Fork: Fox TALAS CTD 120-160mm

Headset: FSA Orbit

Handlebars: Easton Haven Carbon 750mm

Stem: Easton Haven

Shifters: Shimano SLX

Front Derailleur: Shimano XT

Rear Derailleur: Shimano XT

Cassette: Shimano HG62, 11/36 10-speed

Chain: Shimano HG72

Cranks: Shimano XT 24/32/42

Bottom Bracket: Shimano Press-Fit

Pedals: NA

Brakes: Formula RC Tune

Wheels: DT CSW All-Mountain 2.7 straight-pull

Tyres: Schwalbe Hans Dampf 2.35

Saddle: Selle Italia X1 Trail

Seatpost: Easton EA70

Weight: 12.6kg without pedals (18-inch frame 2,234g)

Available Sizes: 16, 18 (tested), 20, 22-inch

Price: $4,999

Distributor: Monza Imports (03) 8327 8080 / www.monzaimports.com.au